Material handling apparatus

ABSTRACT

This invention relates to apparatus for handling material of a solid nature, and particularly long and/or heavy sections of material that are difficult to manoeuvre without mechanical assistance. One application of the invention is in relation to the transport or manoeuvring of logs within forest areas, or within areas at which logs are stored for subsequent treatment.

United States Patent [191 Youl [4 1 Aug. 12, 1975 I MATERIAL HANDLINGAPPARATUS [76] Inventor: John Charles Youl, Symmons Plains,

Perth, Tasmania, Australia [22] Filed: Dec. 5, 1973 [21] Appl. No.:422,079

[30] Foreign Application Priority Data Dec. 6, 1972 Australia 1509/72[52] US. Cl 214/147 G; 294/106 [51] Int. Cl. B66c 1/62 [58] Field ofSearch 214/147 G, 147 R, 92;

[56] References Cited UNITED STATES PATENTS 2,684,166 7/1954 Jarnett294/88 X 3,477,596 11/1969 Michaelson 214/147 G X FOREIGN PATENTS ORAPPLICATIONS 536,048 1/1957 Canada 294/88 Primary E.\'aminerRobert JSpar I Assistant ExaminerGeorge F. Abraham 5 7 ABSTRACT This inventionrelates to apparatus for handling material of a solid nature, andparticularly long and/or heavy sections of material that are difficultto manoeuvre without mechanical assistance. One application of theinvention is in relation to the transport or manoeuvring of logs withinforest areas, or within areas at which logs are stored for subsequenttreatment.

8 Claims, 10 Drawing Figures PATENTEU 2i975 3.899094 SHEET 1 FIG IPATENTED AUG 1 2 975 SHEET MATERIAL HANDLING APPARATUS BREIF DESCRIPTIONOF THE INVENTION 1. Prior Art Manipulation of logs can be an extremelydifficult task, especially in confined areas, and mechanical aids usedprior to this invention have usually been of relatively crude and notparticularly effective construction. For example, one commonly employedmethod involves attachment of a chain between the log and a tractor orother motorized vehicle, and the log is dragged by the vehicle in such away that its leading end tends to gouge into the ground.

SUMMARY OF THE INVENTION It is a principal object of the presentinvention to provide material handling apparatus which is of effectiveconstruction and enables convenient manipulation of relatively heavyobjects such as large logs, even within confined areas.

Apparatus in accordance with the invention is adapted for attachment toa tractor or other prime mover, and as a matter of convenience the termtractor will be hereinafter used as a generic term for all suitableprime movers or motorized vehicles. The apparatus may be arranged fordirect mounting on the tractor, or it may include a wheeled frame whichis con nectable to the tractor through an appropriate coupling. Exampleembodiments of both types of construction will be hereinafter described.

According to the present invention, there is provided material handlingapparatus including, a support frame attachable to a vehicle orprime-mover, a jaw assembly including two gripping jaws arranged forrelative movement towards and away from each other, actuating meansoperable to cause relative movement of said jaws, mounting meansconnecting said jaw assembly to said frame to permit movement of saidassembly relative to said frame, said jaws depending from said mountingmeans to receive material therebetween, and restraining means connectinga lower part of said jaw assembly to said frame so as to limit movementof said assembly relative to said frame.

The following description refers in more detail to these essentialfeatures and further optional features of the invention. To facilitatean understanding of the invention, reference is made to the accompanyingdrawings where these features are illustrated in preferred form. It isto be understood however, that the essential and optional features ofthe invention are not limited to the specific forms of these features asshown in the drawings.

THE DRAWINGS In the drawings:

FIG. 1 is a semi-diagrammatic side elevational view of one embodiment ofthe invention adapted for direct attachment to a tractor or othervehicle;

FIG. 2 is an end view of the embodiment shown in FIG. I;

FIG. 3 is a plan view of the embodiment shown in FIG. 1;

FIG. 4 is an end view of the jaw assembly of the FIG. 1 embodiment,viewed from the left hand side of FIG. 1, parts being omitted forconvenience of illustration;

FIG. 5 is a view similar to FIG. 4 but showing the jaw: in a partiallyclosed position about a log;

FIG. 6 is a view on a reduced scale taken along line 66 of FIG. 4;

FIG. 7 is a view on a reduced scale taken along line 77 of FIG. 4;

FIG. 8 is a plan view of an alternative embodiment 01 the invention inwhich the jaw assembly is mounted or. a wheeled chassis or base frame;

FIGv 9 is a cross-sectional view taken along line 99 of FIG. 8; and

FIG. 10 is a side elevational view of the FIG. 8 embodiment showing thejaw assembly in a raised position, parts being omitted for convenienceof illustration.

DETAILED DESCRIPTION Referring now to the drawings:

A feature of the apparatus is that it includes a jaw assembly 2comprising at least two gripping jaws 3 which are interconnected forrelative movement so as to releasbly grip an object such as a logtherebetween, and are mounted on a support frame or unit 4 in such a wayas to be capable of some movement relative to that frame or unit duringtransport or manipulation of a log. The support frame or unit 4 isconnectable to a tractor in a manner such as to permit controlledraising and lowering of the jaw assembly 2 relative to the ground.Further features of the invention will become apparent from thefollowing detailed description of preferred embodiments.

Referring in particular to the embodiment of FIGS. 1 to 7, the jaws 3are curved and arranged so as to have respective inner concave surfaces5 in opposed relationship. In the operative position of the jaws 3, theydepend from their mounting 6 with the support frame 4, and that mounting6 includes a hookes joint, or other suitable coupling which permitssubstantially universal movement of the jaw assembly 2 relative to thesupport frame 4. The jaws 3 are pivotally connected by pin 7 (see FIG.2) so as to permit relative movement towards and away from each other,and that movement is controlled through actuating means 8 as hereinafterdescribed. If desired each jaw may swing about a separate pivot ratherthan the common pin 7, or relative movement other than pivotal movementmay be employed.

Each jaw 3 of the illustrated embodiment is formed of a blade section 9and a backing flange or rim section 11 which defines the outer surfaceof the jaw 3. The blade section 9 extends inwardly from the rim section11 so that one edge defines the inner concave surface 5 of the jaw 3,and that edge may be formed to assist in obtaining a firm grip on a log.For example, each blade edge 5 may slope as at 12 (see FIGS. 4 to 7),outwardly and rearwardly relative to the intended direction of travel ofthe apparatus, and thereby enable the jaws 3 to bite into a log.

It is further preferred that there is some overlap between the bladesections 9 of the jaws 3 in the fully closed position of the jawassembly 2, so as to permit logs of relatively small cross-sectionalshape to be gripped therebetween. Such overlapping may be achieved inseveral ways, such as by providing a slot or recess in the lower portionof each rim section 11, which slot or recess is disposed and shaped toreceive part of the blade section 9 of the other jaw. The arrangementshould be such that the blade sections 9 lie in close proximity in thefully closed position so as to avoid any tendency for the jaws to twista log gripped therebetween. In the particular construction shown in thedrawings however, such overlap is achieved by providing one of the jaws3 with two laterally spaced blades 9 (see FIG. 7) as that the blade 9 ofthe other jaw 3 can enter into the gap 13 between those two blades.

The support frame 4 of the example directly mounted version of theapparatus, shown in FIGS. 1 to 3 includes a post member 14 adapted to beattached to a tractor in a substantially upright position and having thejaw assembly 2 mounting at or adjacent its upper end. If the tractorincludes a three point linkage type coupling system, it is generallyconvenient to arrange the support post 14 for attachment to that system.In the embodiment shown, the lower end portion of the post 14 is securedto an intermediate portion of a cross member 15 which is connectable atits opposite end portions to the lower links of the tractor coupling(not shown). The upper link of the coupling is connected with anintermediate portion 17 of the support post 14 through any suitablemeans. If desired, the support frame 4 can be strengthened by bracemembers 18 extending between the outer end portions of the cross member15 and the upper end portion of the post 14.

The cross member 15 is connected to the lower links through a pair ofcoupling arms 19, each of which is rigidly secured to the cross member15 at or adjacent a respective end thereof and extends rearwardly fromthat member. The end of each arm 19 remote from the cross member ispivotal by or otherwise connectable to a respective link of the tractorcoupling. If the frame 4 is to be connected to the lower links only ofthe tractor coupling, the opposite end portions of the cross member 15may be attached to or cooperate with those lower links to prevent orlimit relative movement between those links and the coupling arms 19.For example, the end portions of the cross member 15 may be recessed soas to locate about the respective lower links of the tractor coupling.Provision of the coupling arms 19 provides a clearance space between thecross member 15 and the jaws 3 so as to minimize fouling between thecross member 15 and a log held by the jaws 3.

With the arrangement described, the upper end of the post 14, andconsequently the jaw assembly 2, can be moved towards and away from theground by appro priate actuation of the three point linkage system ofthe tractor. Although the post member 14 has been described assubstantially upright in the operative posi tion, it will be seen fromFIG. 1 of the drawings that it actually slopes upwardly and rearwardlyof the tractor, even in the fully raised position of the apparatus, soas to effectively position the jaw assembly 2 rearwardly of the tractorand provide end clearance for a log.

As previously mentioned, the mounting 6 between the jaw assembly 2 andthe support post 14 preferably includes a universal coupling. In theparticular form shown, that coupling includes two yokes 21 and 22 andpivotally connected through a block 23 so that there are two axes ofrotation defined by pins 24 and 25 respectively. Pin 24 extendssubstantially upright, and pin 25 extends generally transverse to boththe pin 24 and the jaw pivot pin 7. The yoke 21 is secured to thesupport post 14 whereas the yoke 22 is secured to the jaw pivot pin 7 ora member attached to that pin. Such an 4 arrangement permits the jawassembly 2 to adopt a large number of positions relative to the supportframe 4 during use, and thereby minimizes strain on the apparatus duringmanipulation of heavy logs.

Restraining means is provided to limit rearward movement of the lowerpart of the jaw assembly 2 relative to the support frame 4 and in thepreferred construction shown that means includes a chain 26 having itsopposite ends secured to a respective jaw 3 as at positions 27 and 28,and being engaged intermediate its ends by an abutment secured to thesupport frame 4. In the illustrated embodiment the abutment includes tworollers or sheaves 29 positioned adjacent respective opposite ends ofthe cross member 15 and being freely rotatable so that the chain 26 canmove relative to the frame 4 to adapt to changes in the jaw assemblyposition. It will be appreciated that another flexible, but relativelynon-extensible, element such as a cable or rope may be substituted forthe chain. The sheaves 29 are preferably mounted so as to be capable oflimited axial movement to allow for changes in the disposition of thechain 26 brought about by raising and lowering of the jaw assembly 2. Inthe illustrated embodiment such a mounting includes a pivot pin 3 onwhich the sheave 29 is mounted, and a bracket 32 secured to the crossmember 15 so as to overlie the sheave 29 with sufficient clearance topermit the desired axial movement.

It is also preferred to provide biasing means whereby the jaw assembly 2is urged into a normal rest position in which it is adapted for readyengagement with a log. Such means is illustrated as including twohelical tension springs 33 each extending between an intermediateportion of a respective one of the brace members 18 and an outer end ofa control arm 34 extending from and connected to the jaw assembly 2. Inthe embodiment shown, the control arm 34 is rigidly connected to the jawpivot pin 7 or a member such as a boss secured to that pin.

Actuating means for the jaw assembly may take any suitable form, buthydraulic actuation is generally found convenient. In the preferredarrangement shown, an actuating arm 35 extends upwardly from the upperend of each jaw 3 and is rigidly secured to the respective blade orblades 9. Each actuating arm 35 extends angularly upwardly and outwardlyso that it and the associated jaw 3 are both disposed on the same sideof the support post 14, but on different sides of the assembly pivot 7.A double-acting hydraulic piston cylinder assembly 8 connects the outerends of the actuating arms 35 and is connectable to the hydraulic systemof the associated tractor so as to be operable to cause relativemovement of the jaws 3 about their pivot 7. An arrangement of this kindpermits the application of extremely high pressures between the jaws 3so that the apparatus is capable of firmly gripping and moving logs oflarge size. It will be appreciated that when a large log is locatedwithin the jaw assembly 2, the actuating arms 35 will be closer togetherthan in the case of a relatively small log, and as a result the lengthof the lever arm between the pivot 7 and the piston-cylinder assembly 8is greater than in the last mentioned case. Thus, the force applied to alog by the jaws 3 is automatically regulated according to the size ofthat log.

An example wheeled frame" version of the apparatus is shown in FIGS. 8to 10 of the drawings, in which construction the support frame 4 iscarried by a base frame or chassis 36 which is mounted on groundengaging wheels 37 located adjacent to a rear end of the chassis, and isconnectable at its front end 38 to the three point linkage system of atractor, or to other mechanism operable to cause up and down movement ofthat end. The cross member 15 of the support frame 4 extends between andis pivotally connected to laterally spaced side members 39 of thechassis 36 so that the support frame 4 can swing relative to the chassis36 about an axis extending substantially parallel to that of the groundengaging wheels 37. That pivotal connection is located intermediate thefront and rear ends of the chassis 36, and a drawbar 51 extends fowardlyfrom the support frame 4 for connection to a ball coupling or othercoupling means provided on the tractor. Preferably, the drawbar 41 isrigidly secured to the cross member 15 of the support frame 4.

With the foregoing arrangement, the jaw assembly 2 is raised and loweredby up and down movement of the front end 38 of the chassis 36, since theground engaging wheels 37 act as a fulcrum and the front end 42 of thedrawbar 41 is held relatively stationary by its connection to thetractor. In addition, the lift provided by the tractor mechanism ismagnified at the jaw assembly 2 because of the lever system defined bythe construction described. That is, there is in effect a double-lift asfollows:

a. When the front end 38 of the chassis is raised as shown in FIG. theposition of the cross member relative to the ground is altered, soeffecting a first lift.

b. As the cross member 15 rises, the angular disposition of the drawbar41 relative to the ground alters because of the stationary connection atthe front end of that bar, and consequently the support post 14 is swungrearwardly about the cross member pivot, thereby effecting a second liftof the jaw assembly 2.

The wheeled frame version illustrated is further modified over theembodiment first described in that the support post 14 has an uprightlower section 43 and a rearwardly extending upper section 44. Inaddition, the biasing means includes three helical tension springs oneof which, 45, extends between the control arm and the support post 14,and the other two, 46, each extending from the support post 14 to anintermediate portion of a respective one of the jaw actuating arms 35.

In each of the embodiments described, the biasing springs serve the dualpurpose of centralizing the jaw assembly 2 about the universal joint 6relative to the intended direction of travel, and also maintainingtension in the restraining chain 26. In the last described embodimenthowever, the spring 45 provides the principal source of tension for thechain 26.

Apparatus as described provides extremely effective means for handlinglogs and other objects, and in practice it is found that such apparatuscauses less fatigue to operators than prior conventional apparatus ofthe same general type. The apparatus enables secure clamping ofrelatively large and small logs, and is constructed in such a way thatminimum strain is imposed on the apparatus and associated machineryduring manipulation of logs.

Finally, it is to be understood that various alterations, modification,and/or additions may be introduced into the constructions andarrangements of parts previously described without'departing from thespirit or ambit of the invention as defined by the appended claims.

1 claim:

1. Material handling apparatus including: a support frame attachable toa vehicle or prime-mover; a jaw assembly comprising two gripping jawswhich are pivotally connected for relative movement towards and awayfrom each other; each said jaw having a blade section which is curved soas to define an inner concave surface arranged in opposed relationshipto the corresponding surface of the other said blade section, and an armrigidly secured to said blade section and extending away therefrom, eachsaid arm and associated blade section being located on the oppositesides respectively of said jaw pivot; actuating means connected betweensaid jaw arms and being operable to cause relative pivotal movement ofsaid jaws; mounting means connecting said jaw assembly to said frame topermit movement of said assembly relative to said frame about at leasttwo axes, one of which extends substantially upright and is transverseto the other of said axes; and flexible restraining meansinterconnecting said blade sections and mounted to freely move around aportion of said frame so as to limit movement of said jaw assembly tosaid frame in one direction about the other of said axes of saidmounting means while allowing free movement of the jaw assembly aboutthe one axis in both directions.

2. Apparatus according to claim 1, wherein each said jaw arm extendsangularly relative to the associated jaw blade section, the arrangementbeing such that movement of said arms away from each other causesmovement of said blade sections towards one another, and the distancebetween said actuating means and said jaw pivot increases as the bladesections separate thereby providing an increased mechanical advantagefor application of a clamping force by said blade sections.

3. Apparatus according to claim 1 wherein said actuating means includesa pressure fluid piston-cylinder assembly having opposite ends portionsconnected to a respective one of said jaw arms.

4. Apparatus according to claim 3, wherein said support frame includes apost member which is connected to and extends upwardly from a crossmember and is connected to said jaw assembly through said mounting meansat an upper end portion, and said frame is connectable to a said vehicleor prime-mover at a lower end portion thereof.

5. Apparatus according to claim 4, wherein the lower end portion of saidframe is constructed for direct connection to a three-point linkagesystem of a tractor.

6. Apparatus according to claim 4, wherein said cross member ispivotally connected to a base frame for movement relative thereto aboutan axis extending substantially parallel to said one axis of saidmounting means axes; said base frame having ground engaging wheelsattached thereto adjacent a rear end thereof, and means for attachmentto lifting mechanism of a vehicle or a prime-mover adjacent a front endthereof; said cross member pivot being located intermediate said frontand rear ends of the base frame; and a drawbar is secured to saidsupport frame to extend forwardly thereof and is arranged for attachmentto a trailer coupling of said vehicle or prime-mover.

7. Apparatus according to claim 6, wherein biasing means extends betweensaid support frame and said jaw assembly to resist relative movement ofsaid jaw assembly and urge that assembly into a normal raised position.

8. Apparatus according to claim 7, wherein said restraining meansincludes a flexible but substantially intermediate section cooperatingwith abutment means connected to said support frame so that lengthwisemovement of said element is permitted but lateral movement of saidintermediate section is resisted in at non-extensible elongated elementhaving opposite ends least one direction.

secured to a respective one of said jaws, and having an

1. Material handling apparatus including: a support frame attachable toa vehicle or prime-mover; a jaw assembly comprising two gripping jawswhich are pivotally connected for relative movement towards and awayfrom each other; each said jaw having a blade section which is curved soas to define an inner concave surface arranged in opposed relationshipto the corresponding surface of the other said blade section, and an armrigidly secured to said blade section and extending away therefrom, eachsaid arm and associated blade section being located on the oppositesides respectively of said jaw pivot; actuating means connected betweensaid jaw arms and being operable to cause relative pivotal movement ofsaid jaws; mounting means connecting said jaw assembly to said frame topermit movement of said assembly relative to said frame about at leasttwo axes, one of which extends substantially upright and is transverseto the other of said axes; and flexible restraining meansinterconnecting said blade sections and mounted to freely move around aportion of said frame so as to limit movement of said jaw assembly tosaid frame in one direction about the other of said axes of saidmounting means while allowing free movement of the jaw assembly aboutthe one axis in both directions.
 2. Apparatus according to claim 1,wherein each said jaw arm extends angularly relative to the associatedjaw blade section, the arrangement being such that movement of said armsaway from each other causes movement of said blade sections towards oneanother, and the distance between said actuating means and said jawpivot increases as the blade sections separate thereby providing anincreased mechanical advantage for application of a clamping force bysaid blade sections.
 3. Apparatus according to claim 1 wherein saidactuating means includes a pressure fluid piston-cylinder assemblyhaving opposite ends portions connected to a respective one of said jawarms.
 4. Apparatus according to claim 3, wherein said support frameincludes a post member which is connected to and extends upwardly from across member and is connected to said jaw assembly through said mountingmeans at an upper end portion, and said frame is connectable to a saidvehicle or prime-mover at a lower end portion thereof.
 5. Apparatusaccording to claim 4, wherein the lower end portion of said frame isconstructed for direct connection to a three-point linkage System of atractor.
 6. Apparatus according to claim 4, wherein said cross member ispivotally connected to a base frame for movement relative thereto aboutan axis extending substantially parallel to said one axis of saidmounting means axes; said base frame having ground engaging wheelsattached thereto adjacent a rear end thereof, and means for attachmentto lifting mechanism of a vehicle or a prime-mover adjacent a front endthereof; said cross member pivot being located intermediate said frontand rear ends of the base frame; and a drawbar is secured to saidsupport frame to extend forwardly thereof and is arranged for attachmentto a trailer coupling of said vehicle or prime-mover.
 7. Apparatusaccording to claim 6, wherein biasing means extends between said supportframe and said jaw assembly to resist relative movement of said jawassembly and urge that assembly into a normal raised position. 8.Apparatus according to claim 7, wherein said restraining means includesa flexible but substantially non-extensible elongated element havingopposite ends secured to a respective one of said jaws, and having anintermediate section cooperating with abutment means connected to saidsupport frame so that lengthwise movement of said element is permittedbut lateral movement of said intermediate section is resisted in atleast one direction.